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TCDD-induced IL-24 secretion in human chorionic stromal cells inhibits placental trophoblast cell migration and invasion. Reprod Toxicol 2022; 108:10-17. [PMID: 34995713 DOI: 10.1016/j.reprotox.2022.01.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/27/2021] [Accepted: 01/02/2022] [Indexed: 12/30/2022]
Abstract
Environmental pollutant dioxins are potentially harmful to pregnant women and can lead to severe adverse outcomes in pregnancy, such as spontaneous abortion and stillbirth. However, little is currently known about the underlying toxicological mechanism. Our previous study reported that the IL-24 gene is a dioxin response gene during 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) treatment. Here, we further tested the effect of TCDD on IL-24 expression in human chorionic stromal cells. We also investigated the effect of IL-24 on the behaviors of human placental trophoblast cells and predicted the potential mechanism underlying these behaviors using functional network analysis. We found that TCDD stimulates IL-24 expression in human chorionic stromal cells in an AhR (aromatic hydrocarbon receptor)-related manner. We also found that IL-24 inhibits the migration and invasion of human placental trophoblast cells, the possible mechanism of which involves thirteen key proteins and mitochondrial function. Our findings suggest that IL-24 is a potential factor induced by TCDD to regulate trophoblast cell invasion, which potentially involves in TCDD-induced abortion.
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Marinello WP, Patisaul HB. Endocrine disrupting chemicals (EDCs) and placental function: Impact on fetal brain development. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2021; 92:347-400. [PMID: 34452690 DOI: 10.1016/bs.apha.2021.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Pregnancy is a critical time of vulnerability for the development of the fetal brain. Exposure to environmental pollutants at any point in pregnancy can negatively impact many aspects of fetal development, especially the organization and differentiation of the brain. The placenta performs a variety of functions that can help protect the fetus and sustain brain development. However, disruption of any of these functions can have negative impacts on both the pregnancy outcome and fetal neurodevelopment. This review presents current understanding of how environmental exposures, specifically to endocrine disrupting chemicals (EDCs), interfere with placental function and, in turn, neurodevelopment. Some of the key differences in placental development between animal models are presented, as well as how placental functions such as serving as a xenobiotic barrier and exchange organ, immune interface, regulator of growth and fetal oxygenation, and a neuroendocrine organ, could be vulnerable to environmental exposure. This review illustrates the importance of the placenta as a modulator of fetal brain development and suggests critical unexplored areas and possible vulnerabilities to environmental exposure.
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Affiliation(s)
- William P Marinello
- Department of Biological Sciences, Center for Human Health and the Environment, North Carolina State University, Raleigh, NC, United States
| | - Heather B Patisaul
- Department of Biological Sciences, Center for Human Health and the Environment, North Carolina State University, Raleigh, NC, United States.
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Augustowska K, Magnowska Z, Kapiszewska M, Gregoraszczuk EL. Is the natural PCDD/PCDF mixture toxic for human placental JEG-3 cell line? The action of the toxicants on hormonal profile, CYP1A1 activity, DNA damage and cell apoptosis. Hum Exp Toxicol 2016; 26:407-17. [PMID: 17623765 DOI: 10.1177/0960327107073119] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The present study was conducted to define the action of a mixture obtained by the extraction and purification of real fly ash, on specific toxicity endpoints, such as hormonal secretion, CYP1A1 expression, DNA damage and cell apoptosis. JEG-3 cell line was exposed in vitro to different doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or Polychlorinated dibenzo-p-dioxin/Polychlorinated dibenzo-P-furan (PCDD/PCDF) mixture. Both TCDD and the mixture decreased hCG secretion, while inhibition of progesterone levels was noted only under the influence of TCDD. The changes in hormone production were not due to the action on cell viability. There were time-dependent differences in CYP1A1 expression in cells exposed to TCDD and PCDD/PCDF mixture. Both TCDD and PCDD/PCDF mixture did not induce the DNA damage, as evaluated by the comet assay. Significantly lower DNA migration from the head of comet into the comet tail was noted after the removal of reagents. The highest efficiency of this process was noted 4 h after the TCDD and 24 h after the PCDD/PCDF mixture removal. These results suggest that the DNA adducts and/or DNA—DNA cross-links were formed. Neither TCDD nor PCDD/PCDF mixture had any effect on cell apoptosis assessed by caspase-3 activity and Hoechst 33258. Taken together, these findings clearly indicate a weaker action of the mixture when compared with TCDD. However, in both cases, their action was not due to the induction of the DNA damage and subsequent cell apoptosis but due to a direct influence of these toxicants on placental hormone production. Human & Experimental Toxicology ( 2007) 26, 407—417
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Affiliation(s)
- Katarzyna Augustowska
- Department of Physiology and Toxicology of Reproduction, Chair of Animal Physiology, Institute of Zoology, Jagiellonian University, Ingardena 6, 30-306 Krakow, Poland
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Fukushima K, Tsukimori K, Li D, Takao T, Morokuma S, Kato K, Seki H, Takeda S, Matsumura S, Wake N. Effect of transient TCDD exposure on immortalized human trophoblast-derived cell lines. Hum Exp Toxicol 2011; 31:550-6. [PMID: 22027506 DOI: 10.1177/0960327111424305] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Low level, antenatal exposure to dioxins is associated with low birth weight, which in turn is associated with long-term sequelae. We exposed the human extravillous cytotrophoblast (EVT) lines HTR-8/SV40 and TCL1 to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and assessed cell growth, invasion, and differentiation. TCDD had no effect on cell proliferation, invasion, or tube formation in Matrigel. The EVT-derived cells expressed a functional aryl hydrocarbon receptor protein; however, TCDD exposure did not alter expression levels of proteins involved in EVT differentiation in early pregnancy, including hypoxia-inducible factor 1A (HIF1A), vascular endothelial growth factor (VEGF), Integrin A1, A6, and AVB3. These results suggest that the reduction in fetal weight induced by dioxin is not the result of vascular remodeling via EVT dysfunction.
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Affiliation(s)
- K Fukushima
- Department of Obstetrics and Gynecology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
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Bondarenko GI, Dambaeva SV, Grendell RL, Hughes AL, Durning M, Garthwaite MA, Golos TG. Characterization of cynomolgus and vervet monkey placental MHC class I expression: diversity of the nonhuman primate AG locus. Immunogenetics 2009; 61:431-42. [PMID: 19468726 PMCID: PMC2810720 DOI: 10.1007/s00251-009-0376-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Accepted: 05/07/2009] [Indexed: 10/20/2022]
Abstract
Nonhuman primates are important animal models for the study of the maternal immune response to implantation within the decidua. The objective of this study was to define the placental expression of major histocompatibility complex (MHC) class I molecules in the cynomolgus (Macaca fascicularis) and vervet (African green) (Chlorocebus aethiops) monkeys. Early pregnancy (d36-42) cynomolgus and vervet placentas were obtained by fetectomy and prepared for histological evaluation. A pan-MHC class I monoclonal antibody demonstrated MHC class I expression in both vervet and cynomolgus placental trophoblasts, with particularly high expression in the villous syncytium, as previously shown in the rhesus and baboon. Placental cytotrophoblasts were isolated by enzymatic dispersion and gradient centrifugation and cultured, and multicolor flow cytometry was used to phenotype cell populations. Culture of isolated villous cytotrophoblasts demonstrated that MHC class I expression was linked to syncytiotrophoblast differentiation. A monoclonal antibody against Mamu-AG, the nonclassical MHC class I homolog of HLA-G in the rhesus monkey, demonstrated intense immunostaining and cell surface expression in cynomolgus placental trophoblasts; however, staining with vervet placenta and cells was low and inconsistent. Reverse transcriptase polymerase chain reaction was used to clone MHC class I molecules expressed in cynomolgus and vervet placentas. While Mafa-AG messenger RNA (mRNA) was readily detectable in cynomolgus placental RNA and was >99% identical at the amino acid level with Mamu-AG, 7/8 Chae-AG complementary DNAs had an unusual 16 amino acid repeat in the alpha1 domain, and all clones had an unexpected absence of the early stop codon at the 3'-end of the mRNA diagnostic for rhesus, cynomolgus, and baboon AG mRNAs, as well as HLA-G. We conclude that while the vervet monkey has retained the placental expression of a primate-specific nonclassical MHC class I locus, diversity is also revealed in this locus expressed at the maternal-fetal interface, thought to participate in placental regulation of the maternal immune response to embryo implantation and pregnancy.
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Affiliation(s)
- Gennadiy I. Bondarenko
- Wisconsin National Primate Research Center, University of Wisconsin, 1223 Capitol Court, Madison, WI 53715-1299, USA
| | - Svetlana V. Dambaeva
- Wisconsin National Primate Research Center, University of Wisconsin, 1223 Capitol Court, Madison, WI 53715-1299, USA
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53715, USA
| | - Richard L. Grendell
- Wisconsin National Primate Research Center, University of Wisconsin, 1223 Capitol Court, Madison, WI 53715-1299, USA
| | - Austin L. Hughes
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
| | - Maureen Durning
- Wisconsin National Primate Research Center, University of Wisconsin, 1223 Capitol Court, Madison, WI 53715-1299, USA
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53715, USA
| | - Mark A. Garthwaite
- Wisconsin National Primate Research Center, University of Wisconsin, 1223 Capitol Court, Madison, WI 53715-1299, USA
- Department of Obstetrics and Gynecology, School of Medicine and Public Health, University of Wisconsin, Madison, WI 53715, USA
| | - Thaddeus G. Golos
- Wisconsin National Primate Research Center, University of Wisconsin, 1223 Capitol Court, Madison, WI 53715-1299, USA
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI 53715, USA
- Department of Obstetrics and Gynecology, School of Medicine and Public Health, University of Wisconsin, Madison, WI 53715, USA
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Baldridge MG, Hutz RJ. Autoradiographic localization of aromatic hydrocarbon receptor (AHR) in rhesus monkey ovary. Am J Primatol 2008; 69:681-91. [PMID: 17171710 DOI: 10.1002/ajp.20381] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the most toxic congener of a large class of manmade pollutants that persist in the environment. TCDD exerts its toxic effects, in part, by binding to its receptor known as the aromatic hydrocarbon receptor (AHR). TCDD is estrogen modulatory and in some systems its receptor associates directly with estrogen receptors via co-activator molecules. TCDD inhibits steroid synthesis in human ovarian granulosa cells and AHR is found in these cells. We have previously shown that AHR is found in whole rhesus monkey ovary, but have yet to establish its location. In the present study, we set out to show that radiolabeled TCDD binds to monkey ovarian follicles and that this binding is receptor mediated. Ovaries from Macaca mulatta were sectioned on a cryostat at 10 micro m; and sections were incubated with either control vehicle, (3)H-TCDD, or (3)H-TCDD plus alpha-naphthoflavone (ANF), a known receptor-blocking agent. Here, we show for the first time specific binding of TCDD to the granulosa cells of antral follicles and other regions of the rhesus monkey ovary. Our data indicate a 60-fold increase in binding with (3)H-TCDD over that of control, and that this binding is reduced to the levels seen in controls with the addition of the competitive antagonist ANF. These findings support the hypothesis that TCDD directly affects primate ovarian function via the AHR.
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Affiliation(s)
- Monika G Baldridge
- Division of Natural and Health Sciences, Carroll College, Waukesha, Wisconsin 53186, USA.
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Lohstroh P, Laughlin L, Gee N, Lasley B. Development, validation and application of a chemiluminescent immunoassay for the measurement of circulating chorionic gonadotropin levels in the laboratory macaque. J Med Primatol 2007; 36:164-9. [PMID: 17517091 DOI: 10.1111/j.1600-0684.2006.00189.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Methods for the measurement of chorionic gonadotropin for pregnancy detection in laboratory macaques chorionic gonadotropin (mCG) have been limited by the paucity of specific reagents. Current assays use reagents developed for human chorionic gonadotropin (hCG) assays and have been limited to radio- or enzyme-immuno assays. METHODS This report describes an automated assay for mCG using reagents for hCG detection that has been adapted to the automated chemiluminescence platform of the Bayer ACS-180 autoanalyzer. RESULTS This automated assay performs similarly to previous assays in terms of sensitivity and specificity but provides additional speed, reliability, and more easily accessible reagents compared with previous formats. CONCLUSIONS When implemented broadly, this assay could provide standardization of mCG measurements for both research and colony management purposes.
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Affiliation(s)
- Pete Lohstroh
- Center for Health and the Environment, University of California, Davis, CA 95616-8615, USA
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Wilken JA, Bedows E. A novel four-amino acid determinant defines conformational freedom within chorionic gonadotropin beta-subunits. Biochemistry 2007; 46:4417-24. [PMID: 17358049 PMCID: PMC2597539 DOI: 10.1021/bi602449d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
On the basis of apparent molecular mass heterogeneity following reducing versus nonreducing SDS-PAGE, we determined that the beta-subunit of macaque (Macaca fascicularis) chorionic gonadotropin (mCG-beta) is more conformationally constrained than the beta-subunit of human chorionic gonadotropin (hCG-beta). The amino acid sequences of these two subunits are 81% identical. To determine the conformational variance source, which was not due to glycosylation differences, we generated a series of hCG-beta-mCG-beta chimeras and identified domains that contributed to CG-beta conformational freedom. We discovered that the CG-beta 54-101 domain contained a small subdomain, residues 74-77, that regulated the conformational freedom of the beta-subunit; i.e., when residues 74-77 were of macaque origin (PGVD), the mutated hCG-beta subunit displayed macaque-like conformational rigidity, and when residues 74-77 were of human origin (RGVN), the mutated mCG-beta subunit displayed human-like conformational freedom and microheterogeneity. Additionally, CG-beta N-terminal domain residues (8, 18, 42, and 46-48) were also found to influence CG-beta conformational freedom when residues 74-77 were of human but not macaque origin. The biological significance of the CG-beta conformational variance was tested using a biological assay that showed that the hCG-alpha-hCG-beta heterodimer facilitated human CG receptor-mediated cAMP-driven luciferase reporter gene activity in HEK cells nearly 1 order of magnitude more effectively than the hCG-alpha-mCG-beta chimera. Together, these data demonstrate that two essential amino acid residues within a four-amino acid subdomain regulated CG-beta conformational freedom and that a conformational difference between hCG-beta and mCG-beta was recapitulated in the context of receptor-mediated CG heterodimer signal transduction activation.
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MESH Headings
- Algorithms
- Amino Acid Sequence
- Animals
- Biological Assay
- Cell Line
- Chorionic Gonadotropin/chemistry
- Chorionic Gonadotropin/genetics
- Chorionic Gonadotropin/metabolism
- Chorionic Gonadotropin, beta Subunit, Human/chemistry
- Chorionic Gonadotropin, beta Subunit, Human/genetics
- Chorionic Gonadotropin, beta Subunit, Human/isolation & purification
- Chorionic Gonadotropin, beta Subunit, Human/metabolism
- Cyclic AMP/metabolism
- Dimerization
- Disulfides/chemistry
- Genes, Reporter
- Humans
- Kinetics
- Luciferases/metabolism
- Macaca fascicularis
- Models, Molecular
- Molecular Sequence Data
- Mutation
- Polymerase Chain Reaction
- Protein Conformation
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Protein Subunits/chemistry
- Protein Subunits/genetics
- Protein Subunits/isolation & purification
- Protein Subunits/metabolism
- Recombinant Proteins/chemistry
- Recombinant Proteins/metabolism
- Signal Transduction
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Affiliation(s)
- Jason A Wilken
- Department of Biochemistry and Molecular Biology and the Eppley Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198
| | - Elliott Bedows
- Department of Biochemistry and Molecular Biology and the Eppley Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198
- * To whom correspondence should be addressed: School of Allied Health Professions, College of Medicine, 984300 Nebraska Medical Center, Omaha, NE 68198-4300 Tel.: 402-559-6074 Fax: 402-559-8112 E-mail:
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Abstract
Hyperglycosylated hCG (hCG-H) is a glycosylation variant of the hormone hCG. Here we review all that is known about this independently functioning molecule. As discussed, it is a very different molecule to the hormone hCG. First, hCG-H is produced by cytotrophoblast cells while regular hCG is made in syncytiotrophoblast cell. Second, it is an autocrine acting directly on the cells which produce it, while regular hCG is an endocrine acting on maternal corpus luteal cells. Third, hCG-H has minimal biological activity in promoting progesterone production compared to regular hCG. Fourth, hCG-H functions unlike regular hCG as an invasion promoter, whether invasion as in choriocarcinoma and testicular germ cell malignancies, or as in implantation of pregnancy. These functions seemingly occur through action on cytotrophoblast cell TGFbeta receptors. Fifth, hCG-H is an essential component for successful human implantation to prevent early pregnancy loss and spontaneous abortion. Sixth, hCG-H is critical for promoting the midtrimester hemochorial implantation, and for preventing preeclampsia. Seventh, measurements of hCG-H have advantages over measurements of regular hCG or total hCG, in detecting pregnancy, pregnancy outcome (failing or term pregnancy), predicting preeclampsia in pregnancy, or as a tumor marker for gestational trophoblastic diseases.
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Affiliation(s)
- L A Cole
- USA hCG Reference Service, Department of Obstetrics and Gynecology, University of New Mexico Health Sciences Center, MSC10-5580, 1 University of New Mexico, 333 Cedar Street, Albuquerque, NM 87131, USA.
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Shi Z, Valdez KE, Ting AY, Franczak A, Gum SL, Petroff BK. Ovarian Endocrine Disruption Underlies Premature Reproductive Senescence Following Environmentally Relevant Chronic Exposure to the Aryl Hydrocarbon Receptor Agonist 2,3,7,8-Tetrachlorodibenzo-p-Dioxin1. Biol Reprod 2007; 76:198-202. [PMID: 17050859 DOI: 10.1095/biolreprod.106.053991] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The aryl hydrocarbon receptor (AHR) mediates the effects of many endocrine disruptors and contributes to the loss of fertility in polluted environments. While previous work has focused on mechanisms of short-term endocrine disruption and ovotoxicity in response to AHR ligands, we have shown recently that chronic exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces premature reproductive senescence in female rats without depletion of ovarian follicular reserves. In the current study, premature reproductive senescence was induced using a range of low-dose exposure to TCDD (0, 1, 5, 50, and 200 ng kg(-1) wk(-1)) beginning in utero and continuing until the transition to reproductive senescence. Doses of 50 and 200 ng TCDD kg(-1) wk(-1) delayed the age at vaginal opening and accelerated the loss of normal reproductive cyclicity with age without depletion of follicular reserves. Serum estradiol concentrations were decreased in a dose-dependent fashion (> or = 5 ng kg(-1) wk(-1)) across the estrous cycle in perisenescent rats still displaying normal cyclic vaginal cytology. Serum FSH, LH, and progesterone profiles were unchanged by TCDD. The loss of reproductive cyclicity following chronic exposure to TCDD was not accompanied by decreased responsiveness to GnRH. Ovarian endocrine disruption is the predominant functional change preceding the premature reproductive senescence induced by chronic exposure to low doses of the AHR-specific ligand TCDD.
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Affiliation(s)
- Zhanquan Shi
- Center for Reproductive Sciences, Department of Internal Medicine, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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Moran FM, Hendrickx AG, Shideler S, Overstreet JW, Watkins SM, Lasley BL. Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on fatty acid availability and neural tube formation in cynomolgus macaque, Macaca fascicularis. ACTA ACUST UNITED AC 2004; 71:37-46. [PMID: 14991909 DOI: 10.1002/bdrb.10056] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is known to alter carbohydrate utilization and specific steps in lipid metabolism. TCDD interacts with estradiol in mobilizing specific fatty acids in chickens that may be a cause of cranial/beak malformations in this species. This study was designed to test the hypothesis that TCDD simultaneously alters critical fatty acid mobilization during early pregnancy and determine if those changes correlate to morphological defects of the developing neural tube in the nonhuman primate. Cynomolgus macaques were treated with a single dose of 4 microg/kg body weight (BW) TCDD on gestational day 15 or 20. Pregnancies were terminated by hysterectomy on gestational day 24-26 and embryos were examined to determine morphology of the developing neural tube. Maternal blood samples were used for fatty acid quantification. Embryos exhibited cellular changes, mainly increased cell death, and intercellular spaces in the neural tube, suggestive of an adverse effect on the developing nervous system. Significant decreases on fatty acid composition were found on some of the eight classes of lipids analyzed. Particularly, a decrease was observed in the n-3 (40-60%) and n-6 (47-75%) essential fatty acids in treated pregnancies compared to untreated controls. These data demonstrate the effect of TCDD in decreasing maternal levels of n-3 and n-6 fatty acids that are considered necessary for normal development in mammals. Since neural tube development is dependent, in part, on n-3 and n-6 fatty acids, it is possible that the limitation of these essential fatty acids in plasma resulted in the observed detrimental effects on early brain development.
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Affiliation(s)
- F M Moran
- Center for Health and the Environment, University of California, Davis, California 95616, USA
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